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      1 #!/usr/bin/perl -w
      2 # ***************************************************************************
      3 # *                                  _   _ ____  _
      4 # *  Project                     ___| | | |  _ \| |
      5 # *                             / __| | | | |_) | |
      6 # *                            | (__| |_| |  _ <| |___
      7 # *                             \___|\___/|_| \_\_____|
      8 # *
      9 # * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel (at] haxx.se>, et al.
     10 # *
     11 # * This software is licensed as described in the file COPYING, which
     12 # * you should have received as part of this distribution. The terms
     13 # * are also available at https://curl.haxx.se/docs/copyright.html.
     14 # *
     15 # * You may opt to use, copy, modify, merge, publish, distribute and/or sell
     16 # * copies of the Software, and permit persons to whom the Software is
     17 # * furnished to do so, under the terms of the COPYING file.
     18 # *
     19 # * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
     20 # * KIND, either express or implied.
     21 # *
     22 # ***************************************************************************
     23 # This Perl script creates a fresh ca-bundle.crt file for use with libcurl.
     24 # It downloads certdata.txt from Mozilla's source tree (see URL below),
     25 # then parses certdata.txt and extracts CA Root Certificates into PEM format.
     26 # These are then processed with the OpenSSL commandline tool to produce the
     27 # final ca-bundle.crt file.
     28 # The script is based on the parse-certs script written by Roland Krikava.
     29 # This Perl script works on almost any platform since its only external
     30 # dependency is the OpenSSL commandline tool for optional text listing.
     31 # Hacked by Guenter Knauf.
     32 #
     33 use Encode;
     34 use Getopt::Std;
     35 use MIME::Base64;
     36 use strict;
     37 use vars qw($opt_b $opt_d $opt_f $opt_h $opt_i $opt_k $opt_l $opt_m $opt_n $opt_p $opt_q $opt_s $opt_t $opt_u $opt_v $opt_w);
     38 use List::Util;
     39 use Text::Wrap;
     40 my $MOD_SHA = "Digest::SHA";
     41 eval "require $MOD_SHA";
     42 if ($@) {
     43   $MOD_SHA = "Digest::SHA::PurePerl";
     44   eval "require $MOD_SHA";
     45 }
     46 eval "require LWP::UserAgent";
     47 
     48 my %urls = (
     49   'nss' =>
     50     'https://hg.mozilla.org/projects/nss/raw-file/tip/lib/ckfw/builtins/certdata.txt',
     51   'central' =>
     52     'https://hg.mozilla.org/mozilla-central/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
     53   'aurora' =>
     54     'https://hg.mozilla.org/releases/mozilla-aurora/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
     55   'beta' =>
     56     'https://hg.mozilla.org/releases/mozilla-beta/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
     57   'release' =>
     58     'https://hg.mozilla.org/releases/mozilla-release/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
     59 );
     60 
     61 $opt_d = 'release';
     62 
     63 # If the OpenSSL commandline is not in search path you can configure it here!
     64 my $openssl = 'openssl';
     65 
     66 my $version = '1.27';
     67 
     68 $opt_w = 76; # default base64 encoded lines length
     69 
     70 # default cert types to include in the output (default is to include CAs which may issue SSL server certs)
     71 my $default_mozilla_trust_purposes = "SERVER_AUTH";
     72 my $default_mozilla_trust_levels = "TRUSTED_DELEGATOR";
     73 $opt_p = $default_mozilla_trust_purposes . ":" . $default_mozilla_trust_levels;
     74 
     75 my @valid_mozilla_trust_purposes = (
     76   "DIGITAL_SIGNATURE",
     77   "NON_REPUDIATION",
     78   "KEY_ENCIPHERMENT",
     79   "DATA_ENCIPHERMENT",
     80   "KEY_AGREEMENT",
     81   "KEY_CERT_SIGN",
     82   "CRL_SIGN",
     83   "SERVER_AUTH",
     84   "CLIENT_AUTH",
     85   "CODE_SIGNING",
     86   "EMAIL_PROTECTION",
     87   "IPSEC_END_SYSTEM",
     88   "IPSEC_TUNNEL",
     89   "IPSEC_USER",
     90   "TIME_STAMPING",
     91   "STEP_UP_APPROVED"
     92 );
     93 
     94 my @valid_mozilla_trust_levels = (
     95   "TRUSTED_DELEGATOR",    # CAs
     96   "NOT_TRUSTED",          # Don't trust these certs.
     97   "MUST_VERIFY_TRUST",    # This explicitly tells us that it ISN'T a CA but is otherwise ok. In other words, this should tell the app to ignore any other sources that claim this is a CA.
     98   "TRUSTED"               # This cert is trusted, but only for itself and not for delegates (i.e. it is not a CA).
     99 );
    100 
    101 my $default_signature_algorithms = $opt_s = "MD5";
    102 
    103 my @valid_signature_algorithms = (
    104   "MD5",
    105   "SHA1",
    106   "SHA256",
    107   "SHA384",
    108   "SHA512"
    109 );
    110 
    111 $0 =~ s@.*(/|\\)@@;
    112 $Getopt::Std::STANDARD_HELP_VERSION = 1;
    113 getopts('bd:fhiklmnp:qs:tuvw:');
    114 
    115 if(!defined($opt_d)) {
    116     # to make plain "-d" use not cause warnings, and actually still work
    117     $opt_d = 'release';
    118 }
    119 
    120 # Use predefined URL or else custom URL specified on command line.
    121 my $url;
    122 if(defined($urls{$opt_d})) {
    123   $url = $urls{$opt_d};
    124   if(!$opt_k && $url !~ /^https:\/\//i) {
    125     die "The URL for '$opt_d' is not HTTPS. Use -k to override (insecure).\n";
    126   }
    127 }
    128 else {
    129   $url = $opt_d;
    130 }
    131 
    132 my $curl = `curl -V`;
    133 
    134 if ($opt_i) {
    135   print ("=" x 78 . "\n");
    136   print "Script Version                   : $version\n";
    137   print "Perl Version                     : $]\n";
    138   print "Operating System Name            : $^O\n";
    139   print "Getopt::Std.pm Version           : ${Getopt::Std::VERSION}\n";
    140   print "MIME::Base64.pm Version          : ${MIME::Base64::VERSION}\n";
    141   print "LWP::UserAgent.pm Version        : ${LWP::UserAgent::VERSION}\n" if($LWP::UserAgent::VERSION);
    142   print "LWP.pm Version                   : ${LWP::VERSION}\n" if($LWP::VERSION);
    143   print "Digest::SHA.pm Version           : ${Digest::SHA::VERSION}\n" if ($Digest::SHA::VERSION);
    144   print "Digest::SHA::PurePerl.pm Version : ${Digest::SHA::PurePerl::VERSION}\n" if ($Digest::SHA::PurePerl::VERSION);
    145   print ("=" x 78 . "\n");
    146 }
    147 
    148 sub warning_message() {
    149   if ( $opt_d =~ m/^risk$/i ) { # Long Form Warning and Exit
    150     print "Warning: Use of this script may pose some risk:\n";
    151     print "\n";
    152     print "  1) If you use HTTP URLs they are subject to a man in the middle attack\n";
    153     print "  2) Default to 'release', but more recent updates may be found in other trees\n";
    154     print "  3) certdata.txt file format may change, lag time to update this script\n";
    155     print "  4) Generally unwise to blindly trust CAs without manual review & verification\n";
    156     print "  5) Mozilla apps use additional security checks aren't represented in certdata\n";
    157     print "  6) Use of this script will make a security engineer grind his teeth and\n";
    158     print "     swear at you.  ;)\n";
    159     exit;
    160   } else { # Short Form Warning
    161     print "Warning: Use of this script may pose some risk, -d risk for more details.\n";
    162   }
    163 }
    164 
    165 sub HELP_MESSAGE() {
    166   print "Usage:\t${0} [-b] [-d<certdata>] [-f] [-i] [-k] [-l] [-n] [-p<purposes:levels>] [-q] [-s<algorithms>] [-t] [-u] [-v] [-w<l>] [<outputfile>]\n";
    167   print "\t-b\tbackup an existing version of ca-bundle.crt\n";
    168   print "\t-d\tspecify Mozilla tree to pull certdata.txt or custom URL\n";
    169   print "\t\t  Valid names are:\n";
    170   print "\t\t    ", join( ", ", map { ( $_ =~ m/$opt_d/ ) ? "$_ (default)" : "$_" } sort keys %urls ), "\n";
    171   print "\t-f\tforce rebuild even if certdata.txt is current\n";
    172   print "\t-i\tprint version info about used modules\n";
    173   print "\t-k\tallow URLs other than HTTPS, enable HTTP fallback (insecure)\n";
    174   print "\t-l\tprint license info about certdata.txt\n";
    175   print "\t-m\tinclude meta data in output\n";
    176   print "\t-n\tno download of certdata.txt (to use existing)\n";
    177   print wrap("\t","\t\t", "-p\tlist of Mozilla trust purposes and levels for certificates to include in output. Takes the form of a comma separated list of purposes, a colon, and a comma separated list of levels. (default: $default_mozilla_trust_purposes:$default_mozilla_trust_levels)"), "\n";
    178   print "\t\t  Valid purposes are:\n";
    179   print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_mozilla_trust_purposes ) ), "\n";
    180   print "\t\t  Valid levels are:\n";
    181   print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_mozilla_trust_levels ) ), "\n";
    182   print "\t-q\tbe really quiet (no progress output at all)\n";
    183   print wrap("\t","\t\t", "-s\tcomma separated list of certificate signatures/hashes to output in plain text mode. (default: $default_signature_algorithms)\n");
    184   print "\t\t  Valid signature algorithms are:\n";
    185   print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_signature_algorithms ) ), "\n";
    186   print "\t-t\tinclude plain text listing of certificates\n";
    187   print "\t-u\tunlink (remove) certdata.txt after processing\n";
    188   print "\t-v\tbe verbose and print out processed CAs\n";
    189   print "\t-w <l>\twrap base64 output lines after <l> chars (default: ${opt_w})\n";
    190   exit;
    191 }
    192 
    193 sub VERSION_MESSAGE() {
    194   print "${0} version ${version} running Perl ${]} on ${^O}\n";
    195 }
    196 
    197 warning_message() unless ($opt_q || $url =~ m/^(ht|f)tps:/i );
    198 HELP_MESSAGE() if ($opt_h);
    199 
    200 sub report($@) {
    201   my $output = shift;
    202 
    203   print STDERR $output . "\n" unless $opt_q;
    204 }
    205 
    206 sub is_in_list($@) {
    207   my $target = shift;
    208 
    209   return defined(List::Util::first { $target eq $_ } @_);
    210 }
    211 
    212 # Parses $param_string as a case insensitive comma separated list with optional whitespace
    213 # validates that only allowed parameters are supplied
    214 sub parse_csv_param($$@) {
    215   my $description = shift;
    216   my $param_string = shift;
    217   my @valid_values = @_;
    218 
    219   my @values = map {
    220     s/^\s+//;  # strip leading spaces
    221     s/\s+$//;  # strip trailing spaces
    222     uc $_      # return the modified string as upper case
    223   } split( ',', $param_string );
    224 
    225   # Find all values which are not in the list of valid values or "ALL"
    226   my @invalid = grep { !is_in_list($_,"ALL",@valid_values) } @values;
    227 
    228   if ( scalar(@invalid) > 0 ) {
    229     # Tell the user which parameters were invalid and print the standard help message which will exit
    230     print "Error: Invalid ", $description, scalar(@invalid) == 1 ? ": " : "s: ", join( ", ", map { "\"$_\"" } @invalid ), "\n";
    231     HELP_MESSAGE();
    232   }
    233 
    234   @values = @valid_values if ( is_in_list("ALL",@values) );
    235 
    236   return @values;
    237 }
    238 
    239 sub sha256 {
    240   my $result;
    241   if ($Digest::SHA::VERSION || $Digest::SHA::PurePerl::VERSION) {
    242     open(FILE, $_[0]) or die "Can't open '$_[0]': $!";
    243     binmode(FILE);
    244     $result = $MOD_SHA->new(256)->addfile(*FILE)->hexdigest;
    245     close(FILE);
    246   } else {
    247     # Use OpenSSL command if Perl Digest::SHA modules not available
    248     $result = `"$openssl" dgst -r -sha256 "$_[0]"`;
    249     $result =~ s/^([0-9a-f]{64}) .+/$1/is;
    250   }
    251   return $result;
    252 }
    253 
    254 
    255 sub oldhash {
    256   my $hash = "";
    257   open(C, "<$_[0]") || return 0;
    258   while(<C>) {
    259     chomp;
    260     if($_ =~ /^\#\# SHA256: (.*)/) {
    261       $hash = $1;
    262       last;
    263     }
    264   }
    265   close(C);
    266   return $hash;
    267 }
    268 
    269 if ( $opt_p !~ m/:/ ) {
    270   print "Error: Mozilla trust identifier list must include both purposes and levels\n";
    271   HELP_MESSAGE();
    272 }
    273 
    274 (my $included_mozilla_trust_purposes_string, my $included_mozilla_trust_levels_string) = split( ':', $opt_p );
    275 my @included_mozilla_trust_purposes = parse_csv_param( "trust purpose", $included_mozilla_trust_purposes_string, @valid_mozilla_trust_purposes );
    276 my @included_mozilla_trust_levels = parse_csv_param( "trust level", $included_mozilla_trust_levels_string, @valid_mozilla_trust_levels );
    277 
    278 my @included_signature_algorithms = parse_csv_param( "signature algorithm", $opt_s, @valid_signature_algorithms );
    279 
    280 sub should_output_cert(%) {
    281   my %trust_purposes_by_level = @_;
    282 
    283   foreach my $level (@included_mozilla_trust_levels) {
    284     # for each level we want to output, see if any of our desired purposes are included
    285     return 1 if ( defined( List::Util::first { is_in_list( $_, @included_mozilla_trust_purposes ) } @{$trust_purposes_by_level{$level}} ) );
    286   }
    287 
    288   return 0;
    289 }
    290 
    291 my $crt = $ARGV[0] || 'ca-bundle.crt';
    292 (my $txt = $url) =~ s@(.*/|\?.*)@@g;
    293 
    294 my $stdout = $crt eq '-';
    295 my $resp;
    296 my $fetched;
    297 
    298 my $oldhash = oldhash($crt);
    299 
    300 report "SHA256 of old file: $oldhash";
    301 
    302 if(!$opt_n) {
    303   report "Downloading $txt ...";
    304 
    305   # If we have an HTTPS URL then use curl
    306   if($url =~ /^https:\/\//i) {
    307     if($curl) {
    308       if($curl =~ /^Protocols:.* https( |$)/m) {
    309         report "Get certdata with curl!";
    310         my $proto = !$opt_k ? "--proto =https" : "";
    311         my $quiet = $opt_q ? "-s" : "";
    312         my @out = `curl -w %{response_code} $proto $quiet -o "$txt" "$url"`;
    313         if(@out && $out[0] == 200) {
    314           $fetched = 1;
    315           report "Downloaded $txt";
    316         }
    317         else {
    318           report "Failed downloading via HTTPS with curl";
    319           if(-e $txt && !unlink($txt)) {
    320             report "Failed to remove '$txt': $!";
    321           }
    322         }
    323       }
    324       else {
    325         report "curl lacks https support";
    326       }
    327     }
    328     else {
    329       report "curl not found";
    330     }
    331   }
    332 
    333   # If nothing was fetched then use LWP
    334   if(!$fetched) {
    335     if($url =~ /^https:\/\//i) {
    336       report "Falling back to HTTP";
    337       $url =~ s/^https:\/\//http:\/\//i;
    338     }
    339     if(!$opt_k) {
    340       report "URLs other than HTTPS are disabled by default, to enable use -k";
    341       exit 1;
    342     }
    343     report "Get certdata with LWP!";
    344     if(!defined(${LWP::UserAgent::VERSION})) {
    345       report "LWP is not available (LWP::UserAgent not found)";
    346       exit 1;
    347     }
    348     my $ua  = new LWP::UserAgent(agent => "$0/$version");
    349     $ua->env_proxy();
    350     $resp = $ua->mirror($url, $txt);
    351     if($resp && $resp->code eq '304') {
    352       report "Not modified";
    353       exit 0 if -e $crt && !$opt_f;
    354     }
    355     else {
    356       $fetched = 1;
    357       report "Downloaded $txt";
    358     }
    359     if(!$resp || $resp->code !~ /^(?:200|304)$/) {
    360       report "Unable to download latest data: "
    361         . ($resp? $resp->code . ' - ' . $resp->message : "LWP failed");
    362       exit 1 if -e $crt || ! -r $txt;
    363     }
    364   }
    365 }
    366 
    367 my $filedate = $resp ? $resp->last_modified : (stat($txt))[9];
    368 my $datesrc = "as of";
    369 if(!$filedate) {
    370     # mxr.mozilla.org gave us a time, hg.mozilla.org does not!
    371     $filedate = time();
    372     $datesrc="downloaded on";
    373 }
    374 
    375 # get the hash from the download file
    376 my $newhash= sha256($txt);
    377 
    378 if(!$opt_f && $oldhash eq $newhash) {
    379     report "Downloaded file identical to previous run\'s source file. Exiting";
    380     exit;
    381 }
    382 
    383 report "SHA256 of new file: $newhash";
    384 
    385 my $currentdate = scalar gmtime($filedate);
    386 
    387 my $format = $opt_t ? "plain text and " : "";
    388 if( $stdout ) {
    389     open(CRT, '> -') or die "Couldn't open STDOUT: $!\n";
    390 } else {
    391     open(CRT,">$crt.~") or die "Couldn't open $crt.~: $!\n";
    392 }
    393 print CRT <<EOT;
    394 ##
    395 ## Bundle of CA Root Certificates
    396 ##
    397 ## Certificate data from Mozilla ${datesrc}: ${currentdate} GMT
    398 ##
    399 ## This is a bundle of X.509 certificates of public Certificate Authorities
    400 ## (CA). These were automatically extracted from Mozilla's root certificates
    401 ## file (certdata.txt).  This file can be found in the mozilla source tree:
    402 ## ${url}
    403 ##
    404 ## It contains the certificates in ${format}PEM format and therefore
    405 ## can be directly used with curl / libcurl / php_curl, or with
    406 ## an Apache+mod_ssl webserver for SSL client authentication.
    407 ## Just configure this file as the SSLCACertificateFile.
    408 ##
    409 ## Conversion done with mk-ca-bundle.pl version $version.
    410 ## SHA256: $newhash
    411 ##
    412 
    413 EOT
    414 
    415 report "Processing  '$txt' ...";
    416 my $caname;
    417 my $certnum = 0;
    418 my $skipnum = 0;
    419 my $start_of_cert = 0;
    420 my @precert;
    421 
    422 open(TXT,"$txt") or die "Couldn't open $txt: $!\n";
    423 while (<TXT>) {
    424   if (/\*\*\*\*\* BEGIN LICENSE BLOCK \*\*\*\*\*/) {
    425     print CRT;
    426     print if ($opt_l);
    427     while (<TXT>) {
    428       print CRT;
    429       print if ($opt_l);
    430       last if (/\*\*\*\*\* END LICENSE BLOCK \*\*\*\*\*/);
    431     }
    432   }
    433   elsif(/^# (Issuer|Serial Number|Subject|Not Valid Before|Not Valid After |Fingerprint \(MD5\)|Fingerprint \(SHA1\)):/) {
    434       push @precert, $_;
    435       next;
    436   }
    437   elsif(/^#|^\s*$/) {
    438       undef @precert;
    439       next;
    440   }
    441   chomp;
    442 
    443   # this is a match for the start of a certificate
    444   if (/^CKA_CLASS CK_OBJECT_CLASS CKO_CERTIFICATE/) {
    445     $start_of_cert = 1
    446   }
    447   if ($start_of_cert && /^CKA_LABEL UTF8 \"(.*)\"/) {
    448     $caname = $1;
    449   }
    450   my %trust_purposes_by_level;
    451   if ($start_of_cert && /^CKA_VALUE MULTILINE_OCTAL/) {
    452     my $data;
    453     while (<TXT>) {
    454       last if (/^END/);
    455       chomp;
    456       my @octets = split(/\\/);
    457       shift @octets;
    458       for (@octets) {
    459         $data .= chr(oct);
    460       }
    461     }
    462     # scan forwards until the trust part
    463     while (<TXT>) {
    464       last if (/^CKA_CLASS CK_OBJECT_CLASS CKO_NSS_TRUST/);
    465       chomp;
    466     }
    467     # now scan the trust part to determine how we should trust this cert
    468     while (<TXT>) {
    469       last if (/^#/);
    470       if (/^CKA_TRUST_([A-Z_]+)\s+CK_TRUST\s+CKT_NSS_([A-Z_]+)\s*$/) {
    471         if ( !is_in_list($1,@valid_mozilla_trust_purposes) ) {
    472           report "Warning: Unrecognized trust purpose for cert: $caname. Trust purpose: $1. Trust Level: $2";
    473         } elsif ( !is_in_list($2,@valid_mozilla_trust_levels) ) {
    474           report "Warning: Unrecognized trust level for cert: $caname. Trust purpose: $1. Trust Level: $2";
    475         } else {
    476           push @{$trust_purposes_by_level{$2}}, $1;
    477         }
    478       }
    479     }
    480 
    481     if ( !should_output_cert(%trust_purposes_by_level) ) {
    482       $skipnum ++;
    483     } else {
    484       my $encoded = MIME::Base64::encode_base64($data, '');
    485       $encoded =~ s/(.{1,${opt_w}})/$1\n/g;
    486       my $pem = "-----BEGIN CERTIFICATE-----\n"
    487               . $encoded
    488               . "-----END CERTIFICATE-----\n";
    489       print CRT "\n$caname\n";
    490       print CRT @precert if($opt_m);
    491       my $maxStringLength = length(decode('UTF-8', $caname, Encode::FB_CROAK));
    492       if ($opt_t) {
    493         foreach my $key (keys %trust_purposes_by_level) {
    494            my $string = $key . ": " . join(", ", @{$trust_purposes_by_level{$key}});
    495            $maxStringLength = List::Util::max( length($string), $maxStringLength );
    496            print CRT $string . "\n";
    497         }
    498       }
    499       print CRT ("=" x $maxStringLength . "\n");
    500       if (!$opt_t) {
    501         print CRT $pem;
    502       } else {
    503         my $pipe = "";
    504         foreach my $hash (@included_signature_algorithms) {
    505           $pipe = "|$openssl x509 -" . $hash . " -fingerprint -noout -inform PEM";
    506           if (!$stdout) {
    507             $pipe .= " >> $crt.~";
    508             close(CRT) or die "Couldn't close $crt.~: $!";
    509           }
    510           open(TMP, $pipe) or die "Couldn't open openssl pipe: $!";
    511           print TMP $pem;
    512           close(TMP) or die "Couldn't close openssl pipe: $!";
    513           if (!$stdout) {
    514             open(CRT, ">>$crt.~") or die "Couldn't open $crt.~: $!";
    515           }
    516         }
    517         $pipe = "|$openssl x509 -text -inform PEM";
    518         if (!$stdout) {
    519           $pipe .= " >> $crt.~";
    520           close(CRT) or die "Couldn't close $crt.~: $!";
    521         }
    522         open(TMP, $pipe) or die "Couldn't open openssl pipe: $!";
    523         print TMP $pem;
    524         close(TMP) or die "Couldn't close openssl pipe: $!";
    525         if (!$stdout) {
    526           open(CRT, ">>$crt.~") or die "Couldn't open $crt.~: $!";
    527         }
    528       }
    529       report "Parsing: $caname" if ($opt_v);
    530       $certnum ++;
    531       $start_of_cert = 0;
    532     }
    533     undef @precert;
    534   }
    535 
    536 }
    537 close(TXT) or die "Couldn't close $txt: $!\n";
    538 close(CRT) or die "Couldn't close $crt.~: $!\n";
    539 unless( $stdout ) {
    540     if ($opt_b && -e $crt) {
    541         my $bk = 1;
    542         while (-e "$crt.~${bk}~") {
    543             $bk++;
    544         }
    545         rename $crt, "$crt.~${bk}~" or die "Failed to create backup $crt.~$bk}~: $!\n";
    546     } elsif( -e $crt ) {
    547         unlink( $crt ) or die "Failed to remove $crt: $!\n";
    548     }
    549     rename "$crt.~", $crt or die "Failed to rename $crt.~ to $crt: $!\n";
    550 }
    551 if($opt_u && -e $txt && !unlink($txt)) {
    552   report "Failed to remove $txt: $!\n";
    553 }
    554 report "Done ($certnum CA certs processed, $skipnum skipped).";
    555